Monthly Archives: July 2016

Watching frigate birds soar lifts spirits like nothing else

Published July 30, 2016 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2016 Susan Scott
A flock of great frigate birds rides tradewinds. ©2016 Susan Scott

A flock of great frigate birds rides tradewinds. ©2016 Susan Scott

I had the blues last week. Our little dog, Lucy, died, and the storm spoiled my usual stress reliever of snorkeling. Nor did I feel like walking the beach. Besides when it drizzled, Lucy and I walked there for years. Going alone made me miss her even more.

But then Craig announced he was off to the beach to check the windsurfing conditions. I dragged myself there with him, and as if summoned to lift my spirits, a flock of great frigate birds appeared overhead.

Craig & Lucy. ©2016 Susan Scott

Craig & Lucy. ©2016 Susan Scott

About 15 of the black birds, with wingspans of 6 feet, stayed up high, their bodies looking like cutouts against the gray sky. Three birds, however, drifted so low we could see their faces and determine their sex — one all-black male, two white-chested females.

Oh, how those seabirds rode the wind. They were in their element, gliding up, down, forward and backward without a single flap of wings. So relaxed were the birds in the stormy weather that one of the females began, while floating in midair, to preen her feathers.

We Hawaii residents know that when it comes to flying, frigate birds, or iwa, are tops. Now though, in a study published this month in the journal Science, we find out how these seabirds manage some of their amazing feats.

On an island off Mozambique, researchers attached tiny solar-powered transmitters to 24 adult and 25 juvenile frigate birds to measure their heart rate, wing beats, acceleration, altitude and GPS coordinates. The results are mind-boggling. One adult flew continuously for 48 days, averaging 261 miles per day. Juveniles flew even farther than their parents, one covering 34,000 miles in 185 days. (Earth’s circumference is 25,000 miles.) The young frigate bird rested on islands only a few hours at a time, totaling less than four days during its six-month journey.

Frigate birds ride tradewinds, but to get even better mileage, they take advantage of clouds, formed when warm air rises. Since warm air inside clouds rises even faster, the birds pop in and ride the up escalator, sometimes ascending to an astonishing 13,000 feet.

From that altitude a frigate bird can get up to 30 miles soaring distance, often enough to find another cloud for another free ride.

The birds travel these long distances because they follow migrating tuna, big fish that drive little fish to the surface where frigate birds can snatch them up. Although they sometimes steal meals from other seabirds, frigate birds catch most of their own fish.

There’s nothing like watching frigate birds fly to get my spirit soaring. The birds showed up just when I needed them. I’ll consider their timely appearance as a tribute to a remarkable dog.

Hallucinations from toxin in fish are rare but potent

Published July 23, 2016 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2016 Susan Scott
Bandtail goatfish, or weke pueo (sometimes called weke pahulu), are among the fish that can cause hallucinatory fish poisoning. ©2016 Susan Scott

Bandtail goatfish, or weke pueo (sometimes called weke pahulu), are among the fish that can cause hallucinatory fish poisoning. ©2016 Susan Scott

A Kentucky man emailed that he was doing research on nightmare weke and wondered whether I knew of recent cases here. Because I hadn’t written about this odd illness, also called hallucinatory fish poisoning, for years, I wondered, too.

The term nightmare weke makes it sound as if only goatfish carry this poison. But the rare toxin, origin unknown, is found throughout tropical and temperate waters. Other culprits include convict tangs (manini), chubs (nenue), mullets (ama), coral groupers and rabbitfish (the latter two not found in Hawaii).

In the Mediterranean and eastern Atlantic, the common food fish saupe, or sea bream, has caused hallucinatory fish poisoning. In Arabic the sea bream is known as “the fish that makes dreams.”

Reunion Islanders (Indian Ocean) call a rabbitfish “the fish that inebriates.” Hawaiians named the sometimes hallucinatory bandtail goatfish weke pahulu, meaning “king of ghosts.”

“Ghost” is putting it mildly. The visions that afflict people who eat affected fish are so dreadful, I get the creeps reading about them.

In 1994 a 40-year-old executive ate sea bream in Cannes, France. Severe vomiting that night caused the man to shorten his vacation and drive home. Soon he started hearing animals screaming and stopped when giant insects surrounded the car. After 36 hours in the hospital (with sedation, I hope), the man was fine.

Another Frenchman in 2002 ate sea bream he bought from a fish market. Because he was 90 and feared people would declare him senile, the man suffered terrifying hallucinations of humans screaming and birds shrieking. When the visions disappeared he reported the incident.

These report dates from a poison center in Marseilles show that the toxin is rare in France. It’s rare in Hawaii, too. From 1990 to 2014 the number of cases reported to the Department of Health was 17, the last one in 2011.

The unidentified toxin occurs in both carnivores and algae-eaters, usually in summer. Cooking doesn’t inactivate the poison, which seems to be concentrated in the head. One Hawaii blog offers good advice to mullet and goatfish fishers: “No eat da head.”

In a 1960 medical journal, researchers wrote that information about this syndrome was being suppressed because “Russia was exceedingly interested in nerve drugs such as this.”

I learned that my emailer’s research was not a scientific study as I thought. Rather, he was gathering material for a New York friend making a film about substances in nature that get people high.

You know it’s a crazy world when people consider poisoning themselves and others with a fish.

Report hallucinatory fish poisonings to the state Department of Health. Save the fish for testing.

Reading about coral biology is a difficult, rewarding slog

Published July 16, 2016 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2016 Susan Scott
A healthy, budding coral branch is shown in Bait Reef, Queensland, Australia. ©2016 Susan Scott

A healthy, budding coral branch is shown in Bait Reef, Queensland, Australia. ©2016 Susan Scott

A reader emailed that he has “coral empathy fatigue” from so many reports about bleaching. It happens. A person can take only so much bad news.

This week I had coral biology fatigue because another reader asked me to explain how heat stress causes embedded algae to damage corals’ natural sunscreen. While researching this biochemistry topic, I wished I had a second computer monitor, one to read the studies and the other to look up molecular biology terms. But slow-going as it was, the answer renewed my energy and my empathy.

Reef-building corals, as we know, host plants in their tissues. The corals get food from the plants, called dinoflagellates, and the plants get a place to hang their hats or, in this case, their swim fins. All dinoflagellates have two wiggly structures that propel them through the water.

One-quarter coral head bleached, three-quarters normal. Kailua Bay, Oahu, Hawaii. ©2016 Susan Scott

One-quarter coral head bleached, three-quarters normal. Kailua Bay, Oahu, Hawaii. ©2016 Susan Scott

Baby corals inherit dinos from a parent or get them on the run as both organisms drift through the water looking for a good place to settle down. To accommodate their plant partners, reef corals must set up housekeeping under the tropical sun in clear, shallow water. Such conditions would normally fry, with UV radiation, immobile animals. Corals survive, however, because they make their own sunscreen.

Researchers report that several chemicals in the sunscreens used by people can damage reef corals, but an elegant solution is in the works. Australian scientists are working with a cosmetic company to manufacture corals’ natural sunscreen for human use.

But back to when algae go bad. Embedded dinos multiply when the coral settles down. Corals can control the number of algae in their tissues, but they can’t control how much oxygen each plant produces. Higher-than-normal water temperatures cause some algae species to photosynthesize like crazy, making oxygen four to eight times faster than its coral host can use.

At this rate, oxygen molecules change chemically to a form called oxygen radicals, which interfere with the production of corals’ sunscreen. Radical indeed. Without UV protection the animals will die.

Bleached Coral, North Shore, Oahu, Hawaii. ©2016 Susan Scott

Bleached Coral, North Shore, Oahu, Hawaii. ©2016 Susan Scott

Coral bodies can’t simply spit out their over-excited tenants. Most often the corals shed the inner layer of stomach cells that contain the algae. When (if) the water cools, the coral bodies that survived catch dinos swimming past, deposit them in newly grown stomach linings and carry on.

Best case: The corals get a new plant species that’s more heat-tolerant. (This is the subject of much current research.)

I hope this answers my reader’s question. It didn’t answer mine. My sources say that coral bodies are transparent and the dinoflagellates color them brown. Why then are some reef corals green, pink, purple and blue?

Purple Green
Two corals of the same species in different colors

In the journal Molecular Ecology, I found a 2015 paper titled “Fluorescent protein-mediated colour polymorphism in reef corals; multicopy genes extend the adaptation/acclimation potential to variable light environments.” This article might or might not answer my question.

I’ll have to buy another computer monitor to find out.

‘Mermaid bracelets’ ashore a curious find Down Under

Published July 9, 2016 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2016 Susan Scott

wormsOne of the joys of snorkeling or beach walking in Australia is finding marine animals new to me. It’s also frustrating because being on my sailboat, I often don’t have internet access or the right books on board to look up what I’ve found.

The creature that stumped me on my recent trip appeared on Whitehaven Beach during an extremely low tide. At first glance the thing looked like a line of white seashells tangled up in brown and green seaweed. But when a small wave rolled over the clump, it stayed in place, fixed to the spot.

Down the beach, a longer string of shells and seaweed appeared, then another and another, all streaming behind the receding water like glistening ornaments. Mermaid bracelets, I named them, because a few of the shells in the strands were the forams I wrote about called mermaid pennies (May 28).

I gently scooped sand from around one of the shell ropes and found it anchored a few inches down in the sand. I laid my strand above the break to examine it, and out from the end popped a pair of rust-colored antennae and behind them several fuzzy legs. I had found a bristle worm that collects shells. I’m home now, and, as usual, Google found my mystery worm first try, even with the lame search words “polychete (bristle worms’ scientific name) that makes tubes from shells.” My worm’s name is Diopatra (rhymes with Cleopatra). Members of this group live in self-made tubes of thin, paperlike material onto which they glue small shells, bits of algae and pieces of coral. The worm lives with the lower part of its tube body buried vertically in the sand and the top part drooping head-down over the seafloor, like a candy cane.

Diopatra shell jackets look decorative to us, but for these ambush predators they’re camouflage. When a small invertebrate wanders close to the worm-in-shell-clothing, the worm darts partially from its tube and grabs its prey with sharp jaws. When fresh meat is scarce, the worms eat dead plant and animal tissue.

Hawaii hosts at least two species of Diopatra. These little cross-species-dressers extend a third or more of their length from their tubes to feed in an arc around their anchored base. In some areas the worms’ dense presence between reef and beach stabilizes sand, preventing beach erosion.

These shell-dressed worms are exposed at very low tides, during which times the worms are in danger of drying out and/or getting eaten. I’ve not seen them before, but I’ll now be on the lookout.

I like the rather regal name Diopatra, and found it means “divine habitat” in Greek. For those of us who love walking beaches during low tide at first light, these worms are well named.

When it comes to coral, the story is complicated

Published July 2, 2016 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2016 Susan Scott

DSCN3313News reports about the demise of the Great Barrier Reef are so pervasive that before I left Hawaii to sail there, several people asked me why I wanted to go.

Then I arrived and for six weeks enjoyed the most glorious corals I’ve ever seen.

So what’s the story? It’s complicated.

It’s true that warmer-than-normal water due to El Nino and climate change is seriously stressing the Great Barrier Reef’s corals. It’s not true, however, that over 90 percent of them are dead.

False impressions come from coral bleaching studies with startling titles, confusing statistics and locations that mean little to those unfamiliar with Australia.

DSCN3185

In April, for instance, the Australian Research Council’s Centre of Excellence for Coral Reef Studies issued a media release with the headline, “Only 7 percent of the Great Barrier Reef has avoided coral bleaching.” From this the Huffington Post ran the headline: “93 Percent of the Great Barrier Reef’s Coral is Practically Dead.”

Not so. I sailed and snorkeled in the central section of the reef and saw only one bleached coral patch about 2 feet square.

DSCN3129

Part of the confusion is the term bleaching, the name of a phenomenon involving corals’ embedded algae. Corals host about 10 species of algae, the source of corals’ lovely colors.

Several events occur when ocean temperatures rise, one being that the corals’ algae produce more oxygen, consequently breaking down the creatures’ chemical sunscreen. And so to prevent death from sunburn, the corals oust their algae. Coral colonies look white then because the transparent animals sit in white calcium carbonate cups of their own making. Hence the word bleached.

DSCN3105

Bleaching doesn’t always mean death. Corals also get food by stinging passing animal plankton and can survive on that for some time depending on species and conditions. When the water cools, the colorless corals still alive catch the algae they need from surrounding water. Surviving corals might grow slower after a bleaching event or not reproduce well for a while, but they’re alive.

Coral bleaching and its rapid increase worldwide is a dire warning to the world that the oceans’ plants and animals are in trouble and, therefore, so is every living thing on Earth. As to how many of the Global Barrier Reef’s bleached corals will recover, how many will not and how to best help them get growing again, no one knows for sure. We have no previous experience with what happens when we heat up the entire planet.

The areas in the northern Great Barrier Reef have been hit hardest with bleaching, but all is not lost. I’ve seen some of the central area’s healthy, breathtaking corals. And that’s why I go.